Jeff Bauman, A Boston Bombing Survivor, Testifies In Court About His Memories Of That Day

Walking into a federal courtroom in Boston with two prosthetic legs, Jeff Bauman testified in the Boston Marathon bombing trial Thursday. Dzhokhar Tsarnaev faces 30 federal charges for the April 15, 2013 attack that took both of Bauman's legs. On the second day of the trial, victims took the stand as part of the prosecutor's attempt to portray the agony caused by the bombing.

Dzhokhar, 21, is on trial for detonating one of two pressure-cooker bombs in the attack he allegedly carried out with his brother, Tamerlan, who was killed by police four days after the bombing. Three people were killed at the marathon and another was fatally shot during the manhunt for the brothers. More than 260 were injured at the race. Dzhokhar's attorney admitted his guilt, saying "he did it," so the trial is really about why he did it. While Bauman spoke about his experience that day, Dzhokhar just stared ahead — just like he did during the previous testimonies Wednesday and earlier Thursday.

Bauman explained that he was standing at the marathon finish line, waiting for his girlfriend to run by, when he bumped into a man carrying a backpack weaving through the crowd. In his testimony, he says:

He looked very suspicious. He was alone. He wasn't watching the race. He didn't look like he was having fun.

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Bauman says he turned back to watch the race, but soon after noticing the man, he saw the backpack on the ground. Not long after, he was on the ground and thought it was fireworks making his ears ring. "It smelled like the Fourth of July," he says. Then he looked down at his legs. He says:

I could see my bones and flesh sticking out.

He says he told himself, "This is it. This is the way it's gonna end. I had a great life." People rushed to help him, including Carlos Arredondo who was in the courtroom Thursday, nodding as Bauman testified. In the hosptial, Bauman told a friend, "I saw the kid. I know what happened." The FBI and state police questioned him from his hospital bed and his description of the man the saw helped identify Tamerlan.

Bauman wrote a book, Stronger, about his experience that day and the FBI investigation in which he was a key witness. In the book, he writes that he woke up in the hospital April 16, 2013, not able to speak and asked for a piece of paper. He wrote, "Saw the guy. Looked right at me," initiating the four-day manhunt for the Tsarnaev brothers.

Other victims and Boston police officers testified in Dzhokhar's trial Wednesday and Thursday, including Karen McWatters, who lost a leg and her good friend Krystle Campbell in the bombing. The witnesses detailed their painful experiences to the jury who will eventually decide Dzhokhar's fate in the trial that's expected to last months.